Astronomy:14 Comae Berenices
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| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Coma Berenices |
| Right ascension | 12h 26m 24.06461s[1] |
| Declination | +27° 16′ 05.6845″[1] |
| Apparent magnitude (V) | 4.95[2] |
| Characteristics | |
| Spectral type | F0p[3][4] |
| U−B color index | +0.18[2] |
| B−V color index | +0.277±0.018[5] |
| Astrometry | |
| Radial velocity (Rv) | −2.20[6] km/s |
| Proper motion (μ) | RA: −16.010[1] mas/yr Dec.: −13.412[1] mas/yr |
| Parallax (π) | 12.2564 ± 0.2329[1] mas |
| Distance | 266 ± 5 ly (82 ± 2 pc) |
| Absolute magnitude (MV) | +0.35[7] |
| Details[8] | |
| Mass | 2.4[7] M☉ |
| Radius | 23 R☉ |
| Luminosity | 76.01[5] L☉ |
| Surface gravity (log g) | 3.4[8] cgs |
| Temperature | 7,300 K |
| Rotational velocity (v sin i) | 226[7] km/s |
| Age | 500 Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
14 Comae Berenices is a single[3] star in the northern constellation of Coma Berenices, and is the second brightest[8] member of the Coma Star Cluster.[3] It is a faint star but visible to the naked eye with an apparent visual magnitude of 4.95.[2] Parallax measurements place the star at a distance of about 266 light years.[1]
The spectrum of this star is peculiar and it has been assigned a number of different stellar classifications: A5, F0p, F0 III Sr, F0 vp,[3] F1 IV: np Sr shell,[5] A9 IV np Sr II,[10] F1 IV,[11] and A9 V + shell.[12] Abt & Morrell (1995) designated this a Lambda Boötis star but this was later refuted.[10] No surface magnetic field has been detected on 14 Comae Bernices.[13]
14 Comae Berenices is a well-known[12][8] shell star with a high rate of spin, showing a projected rotational velocity of 226 km/s.[7] This is giving the star an oblate shape with an equatorial bulge that is 12% larger than the polar radius.[4] It is radiating 76[5] times the Sun's luminosity from its photosphere at an effective temperature of 7,300 K.[8]
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Brown, A. G. A. (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics 616: A1. doi:10.1051/0004-6361/201833051. Bibcode: 2018A&A...616A...1G. Gaia DR2 record for this source at VizieR.
- ↑ 2.0 2.1 2.2 Ducati, J. R. (2002). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system". CDS/ADC Collection of Electronic Catalogues 2237. Bibcode: 2002yCat.2237....0D.
- ↑ 3.0 3.1 3.2 3.3 Abou Elazm, M. S. (October 1993), "The composite spectrum of the A type star 14 Comae", Astrophysics and Space Science 208 (1): 1–4, doi:10.1007/BF00658127, Bibcode: 1993Ap&SS.208....1A
- ↑ 4.0 4.1 van Belle, Gerard T. (March 2012), "Interferometric observations of rapidly rotating stars", The Astronomy and Astrophysics Review 20 (1): 51, doi:10.1007/s00159-012-0051-2, Bibcode: 2012A&ARv..20...51V
- ↑ 5.0 5.1 5.2 5.3 Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters 38 (5): 331. doi:10.1134/S1063773712050015. Bibcode: 2012AstL...38..331A.
- ↑ Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters 32 (11): 759–771. doi:10.1134/S1063773706110065. Bibcode: 2006AstL...32..759G.
- ↑ 7.0 7.1 7.2 7.3 Pizzolato, N. et al. (2000). "Evolution of X-ray activity of 1-3 Msun late-type stars in early post-main-sequence phases". Astronomy and Astrophysics 361: 614. Bibcode: 2000A&A...361..614P.
- ↑ 8.0 8.1 8.2 8.3 8.4 Dominy, J. F.; Smith, M. A. (1977). "A spectroscopic study of 14 Comae and other A-type shell stars". Astrophysical Journal 217: 494. doi:10.1086/155598. Bibcode: 1977ApJ...217..494D.
- ↑ "14 Com". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=14+Com.
- ↑ 10.0 10.1 Murphy, Simon J. et al. (October 2015), "An Evaluation of the Membership Probability of 212 λ Boo Stars. I. A Catalogue", Publications of the Astronomical Society of Australia 32: 43, doi:10.1017/pasa.2015.34, e036, Bibcode: 2015PASA...32...36M
- ↑ Gray, R. O. et al. (2001). "The Physical Basis of Luminosity Classification in the Late A-, F-, and Early G-Type Stars. I. Precise Spectral Types for 372 Stars". The Astronomical Journal 121 (4): 2148. doi:10.1086/319956. Bibcode: 2001AJ....121.2148G.
- ↑ 12.0 12.1 Abt, Helmut A.; Willmarth, Daryl W. (August 1999), "Binaries in the Praesepe and Coma Star Clusters and Their Implications for Binary Evolution", The Astrophysical Journal 521 (2): 682–690, doi:10.1086/307569, Bibcode: 1999ApJ...521..682A
- ↑ Kudryavtsev, D. O. et al. (November 2006). "New magnetic chemically peculiar stars". Monthly Notices of the Royal Astronomical Society 372 (4): 1804–1828. doi:10.1111/j.1365-2966.2006.10994.x. Bibcode: 2006MNRAS.372.1804K.
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